Robins' return is familiar sight during spring

Those harbingers of spring, American robins, are enthusiastically back, even though spring is a little more reluctant. Robins are the most widely recognized bird in North America, as they are found nearly throughout the continent. Even though they are common, most people really don't know much about them.

Males and females are very similar in color, although the females are usually a little more washed-out looking. The first spring arrivals are males, who arrive a few days to two weeks before the females to claim a territory.

Most people are familiar with their song "cheerily, chirrup." They are usually the first bird to start singing before dawn. They also are often the last bird singing after sunset. Unlike many birds that seek shelter before a storm, robins like to sing as the rain approaches.

Robins are adept at getting around. They can fly up to 36 mph. On the ground, most species of birds hop, as that is the best way to get around in the trees in which they spend most of their time. Robins spend a lot of time on the ground and are one of the few species that can run as well as hop.

Male robins are notoriously territorial but seem to lack a concept of self. They will attack their own reflection in a window to the point of neglecting safeguarding their nest. Fortunately, once the babies hatch, the father is too busy feeding them to chase reflections.

Both sexes will vigorously defend their nest. Many cats have been chased off by these feisty, relatively small birds. Studies have suggested that robins are less likely to attack you if you look them squarely in the eye while approaching their nest. If they do attack, ignore this advice and protect your eyes. A robin will go after the top of your head, but a wingtip may catch your eye.

Age and albinism

All robins roost together in the winter, with some of these roosts numbering in the hundreds of thousands. During the nesting season, the females sit on their nests while the males roost together. Young from the first brood of the year will join the males while the females sit on their second and third broods.

The oldest living robin ever recorded was 13 years and 11 months old. This is quite an accomplishment when you realize that only 25 percent of babies make it to the end of the year in which they were hatched, and 50 percent of the remaining robin population dies each year.

A 1965 study found that 8.2 percent of reported albino (including partial albino) birds were robins. This is a higher percentage than any other reported species.

This may be due to the fact that robins are partial migrators, with many of them moving a relatively short distance from their breeding grounds for the winter. Albino feathers are not as strong as pigmented feathers. If robins were neotropical migrants, like the majority of our songbirds, and traveled long distances, natural selection would place pressure against albinism.

Then again, it could simply be that robins are human-oriented, very visible, and very common and that because of that, people simply see more albinos than in other species.

Protective bristles

Most of us remember from our childhood captures that beetles, grasshoppers and many other insects have rather sharp, prickly feet. Imagine being a bird and unable to protect your eyes while using your bill to grab tasty morsels with little needles at the end of their legs. To protect their eyes, robins evolved a unique adaptation called "rictal bristles," which are specialized feathers that project from their bill. These bristles help to keep body parts of their prey in their mouth.

Because overwintered berries and fruits are often fermented, robins often get intoxicated if they have too many when they return in the spring. It is not uncommon to see a drunken robin stagger and fall over. They also risk injury from flying into things.

Worms are not native to North America. Those of you who have attempted to wrench a reluctant night crawler from the ground know how strong these little critters can be. Robins just so happen to have a bill shape and body size conducive to worm hunting. When worms arrived, robins quickly learned how to snatch these slippery, squirmy creatures out of the ground.

Robins learned to like worms so much that instead of laying eggs early in the morning, when most birds do, they take advantage of the abundant worms and eat instead. When the worms retreat deeper into the ground as the day warms, the robins then tend to egg-laying.

The next time we have a storm and you hear a robin singing, watch for its funny worm-catching antics when the storm ends. I'm hoping this familiar bird is now even more familiar to you.

This is the opinion of Jan Bergstrom, who appears the first Sunday of each month in Our Woods & Waters. She welcomes questions and comments at janbergstrom2@gmail.com.